This invention relates to smoking or flavor generating articles of the type in which a heat source provides hot air for drawing through a flavor bed to release tobacco or other flavors, and more particularly to a reflector sleeve for use with the heat source in such an article.
Copending, commonly-assigned U.S. patent application Ser. No. 07/222,961, filed July 22, 1988, still pending, copending, commonly-assigned U.S. patent application Ser. No. 07/223,153, filed July 22, 1988, now U.S. Pat. No. 4,991,606, copending, commonly-assigned U.S. patent application Ser. No. 07/315,822, filed Jan. 27, 1989, now U.S. Pat. No. 4,966,171, and copending, commonly-assigned U.S. patent application Ser. No. 07/571,730 filed Aug. 24, 1990, each of which is hereby incorporated by reference in its entirety, all describe smoking or flavor generating articles that can mimic conventional cigarettes. In each of said applications, the article described has an active element that includes a sleeve in which is suspended a heat source containing carbon, a metal nitride, or some combination thereof, which burns to produce substantially only carbon dioxide. Such a heat source is described in copending, commonly assigned U.S. patent applications Ser. No. 07/223,232, filed July 22, 1988 and Ser. No. 07/443,636, filed Nov. 29, 1989, each of which is hereby incorporated by reference in its entirety. The active element also includes a material, such as tobacco-containing pellets of the type described in copending U.S. patent application Ser. No. 07/222,831, filed July 22, 1988, now U.S. Pat. No. 4,981,522, which is hereby incorporated by reference in its entirety, that releases tobacco or other flavors when heated by the drawing of air through the heat source and then through it.
In the articles described in said above-incorporated copending applications, the heat source is suspended in a sleeve at the distal end of the article. In each case the sleeve is preferably reflectorized in order to radiate heat back to the heat source to keep it hot enough to maintain combustion, and the sleeve is preferably air permeable in order to admit air to support combustion. The sleeve can be inherently air permeable, or it can be rendered air permeable by perforation.
Several different sleeve constructions are described in the above-incorporated applications. In one application, a ceramic sleeve of controlled porosity is lined with a perforated metal foil layer. In another, a layer of perforated metal foil is overwrapped by a layer of porous or perforated paper. In both of these constructions, a stainless steel or other reflective metallic end cap is added after the sleeve is assembled. The end cap prevents dropout of a hot heat source if it becomes loose, cracked or broken. In still another construction, a drawn aluminum cup is used, eliminating the need for a separate end cap. The aluminum cup in that construction is fluted to provide air ducts, as well as to match the inside and outside thicknesses of other components of the article.
The first two of the above described constructions requires several assembly steps because of the different layers involved and the use of a separate end cap, and all three constructions must be assembled at a separate location from the article, and then brought to the location where the article is assembled. The various assembly steps may require a number of different machines as well.
It would be desirable to be able to provide a reflector sleeve for a smoking or flavor generating article that has an integral end cap. It would also be desirable to be able to provide such a sleeve that could be formed as part of the assembly of the article.